Signs of lactose intolerance usually appear within two hours of consuming milk products.
Lactose intolerance is a condition in which a person is unable to digest the lactose, or sugar, present in milk. It occurs when the body does not have enough of the intestinal enzyme lactase. If you have lactose intolerance, you may experience one or more of the following symptoms 30 minutes to two hours after consuming a milk-containing or milk-based product:
Abdominal bloating, pain or cramps
Borborygmi (rumbling in the stomach)
Flatulence or gas
nausea, which may be accompanied by vomiting.
Whether or not to eat dairy products
If you experience other symptoms, including hives or wheezing, immediately after consuming milk, you likely have a milk allergy, i.e. you are allergic to milk protein . Milk allergy is more common in babies and children and can cause anaphylaxis, a serious and life-threatening reaction. Lactose intolerance, on the other hand, is generally harmless, although the symptoms can be very bothersome. The severity of symptoms varies from person to person, depending on how much lactose you can tolerate. However, it is usually possible to manage the disease by avoiding dairy products.
According to a meta-analysis published in 2017, it is estimated that 68% of the world’s population is lactose intolerant. The disease tends to appear over time and does not go away. Commercially made forms of the enzyme lactase are available over-the-counter, but these treatments usually do not provide full relief of symptoms. Dairy products are an important part of a balanced diet, as they provide the body with calcium, protein and various vitamins, including A, B12 and D.
If you no longer consume dairy products but do not supplement your diet with foods containing these essential minerals and vitamins, you are at risk of complications, including low bone mineral density called osteopenia, which can lead to osteoporosis, a bone disease that increases the risk of fractures. Ask your doctor or dietitian if you’re getting the nutrients you need, and especially if you need to find other ways to meet your essential calcium and vitamin D needs.
Lactose intolerance tests
A simple method to determine if you have lactose intolerance is called the “milk challenge”. Drink a glass of milk after not consuming any dairy products for several days. If you experience the characteristic symptoms of lactose intolerance listed above, you are likely to have it.
Your doctor also has a number of tests to determine if you have lactose intolerance:
Hydrogen breath test
Lactose intolerance blood test
Stool acidity test
The hydrogen breath test is a simple and generally accurate technique for diagnosing lactose intolerance.
Can you become lactose intolerant later in life?
Your doctor will ask you to drink a liquid containing a known amount of lactose, then breathe into a device that measures the amount of hydrogen in your breath. If you are lactose intolerant, the bacteria in your intestines will ferment the sugar and release the hydrogen and/or methane that the device can detect.
Your doctor may also perform a blood test or even a biopsy, although these two tests are rarely used today. A stool acidity test is available for infants and children who cannot have other tests. This test detects lactose intolerance by looking for an increase in stool acidity or pH, caused by fermentation of lactose by bacteria in the colon.